one last post with mostly stock stuff even a q-jet
DYNO TESTING
The heads were tested on a 455 (now 468) engine mounted on a Super Flow SF-901 dynamometer. Jeff usually does not acknowledge the torque figure at the start of the pull because it could be incorrect. So the reading was taken at 3,900 to get a more realistic number on the 6X head pull. The correction factor for testing was 1.083.
BEST PULL: 6X HEADS WITH Q-JET
RPM....TQ....HP
3,500 524.5 349.5
3,600 514.4 352.6
3,700 518.4 365.2
3,800 521.3 377.1
3,900 522.0 387.6
4,000 521.2 397.0
4,100 517.2 404.0
4,200 502.2 401.6
4,300 495.9 406.0
4,400 504.7 422.8
4,500 509.0 436.1
4,600 506.0 443.2
4,700 497.6 445.3
4,800 494.3 451.7
4,900 486.4 453.8
5,000 471.4 448.8
5,100 457.7 444.4
5,200 455.8 451.3
5,300 451.2 455.4
5,400 439.2 451.5
5,500 427.1 447.2
BEST PULL: KAUFFMAN ALUMINUM HEADS WITH Q-JET
RPM ....TQ....HP
3,500 547.2 364.6
3,600 549.5 376.7
3,700 548.1 386.2
3,800 548.4 396.8
3,900 548.6 407.4
4,000 548.3 417.6
4,100 546.3 426.4
4,200 545.9 436.6
4,300 543.4 444.9
4,400 539.4 451.9
4,500 537.4 460.4
4,600 534.9 468.5
4,700 532.5 476.5
4,800 523.5 478.5
4,900 518.9 484.1
5,000 511.4 486.9
5,100 501.6 487.1
5,200 492.7 487.8
5,300 485.4 489.8
5,400 478.1 491.6
5,500 471.9 494.2
5,600 463.6 494.3
ABOUT THE DYNO ENGINE
Block: .060-over 455 = 468 ci
Crank: Stock nodular iron, 4.21 stroke, rotating assembly balanced
Rods: Crower forged steel, stock 6.625 length
Oiling System: Stock
Pistons: TRW forged, flat-top, exactly-zero deck
Compression Ratio: 9.95:1
Heads: 6X, 2.11/1.77 valves
Mods: Port-matched, cleaned up, bowl work, bigger exhaust valves
Valve Job: Custom, multi angles
Chamber Size: 91 ccs
Head Gasket: Fel-Pro 8518
Rocker Arms: Crane, 1.65:1 roller, Rhoads lifters
Cam: Crower PN 60919, hydraulic
Duration at .050: 231º/240º
Lift: .517/.517 with 1.65:1 rockers
Lobe Separation Angle: 113º
Installed Position: Intake set at 109º centerline
Intake Manifold: OEM '68 cast iron
Mods: Reworked at carb flange to fit both bolt patterns, Q-jet and Holley
Carb: Q-jet, .073 primary jets, .048 custom-machined secondary rods
Carb: Holley, custom .093 primary jets, custom .097 secondary jets
Distributor: GM HEI, 20º mechanical advance
Timing: 30º total, all in by 2,500 rpm
Spark Plugs: AC R45TSX